Most gambling casinos and other gaming locations contain a large number of gaming machines which typically accept one or more coins as wagers and dispense winnings in coin from a hopper. Because there is a constant inflow and outflow of currency through such machines, it is important to keep careful and accurate records of game activity, such as the total machine payout, the value of wagers placed at the machine and the value of any currency used to purchase credits for wagering. Moreover, gambling regulatory commissions in many jurisdictions require casino operators to keep very specific accounting data with regard to their gaming machines. Therefore, it has been desirable to automate gaming machine accounting to improve reliability and reduce costs.
Traditionally, slot machines and other types of gambling machines accepted and dispensed only coins. For these machines, the game accounting problem is greatly simplified. Coin input by the user always becomes part of game activity, i.e., players risk all of the coins they insert into the machine. Therefore, game activity could be monitored simply by tracking coin inflows and outflows from the machine. In addition, the change in the level of coins in the coin payout hopper, which is impractical to measure directly, could be inferred quite easily by subtracting the sum of the total game outflow and the total number of coins diverted to the game's drop bucket from the total number of coins inserted in the machine. Similarly, the calculation of game win percentage is given by the ratio of coin outflow to coin inflow.
Today, the increased sophistication of gaming machine technology has greatly increased player options. For example, gaming machines have been devised which can accept currency in forms other than coin. An example of a gaming machine that is equipped with a bill acceptor for accepting paper currency is 10 described in U.S. Pat. No. 5,113,990. Indeed, gaming machine technology has advanced to such a stage that it is now possible for gaming machines to accept items of monetary value in forms other than cash. For example, slot machines and video gaming machines are now being built which are equipped with magnetic card readers or smart card readers that can accept monetary credit from a player account stored on casino credit cards, or from the player's commercial credit card. An example of such a gaming machine is disclosed in U.S. Pat. No. 5,038,022. In such machines, winnings can be credited to the card instead of being paid out in coin. Other forms of cashless gaming machines available today include machines that accept bar coded coupons and video lottery machines that offer many games, often of various kinds, within a single cabinet and which pay winnings on printed vouchers issued by the machine.
The addition of these new forms of wagering and payout instruments has greatly complicated the machine accounting problem. For example, it is now possible for a player to input dollar bills or credit from a credit card into a gaming machine and cash out immediately without placing any bets. In this case, the game credit purchased and cashed in by a player has never become part of game activity. Because not all coins dispensed by a gaming machine are the result of game winnings, monitoring game activity is no longer a simple matter of tracing coin outflows and coin inflows. Accordingly, the calculation of hopper level and game win percentage must take into account "vended credits", i.e., credits purchased but not risked
The failure to account for vended credits means that game win percentage calculations can be compromised when, for example, a note or credit card acceptor is added to a coin gaming machine. In many of these retrofit installations, when the gaming machine accepts currency other than coin, a meter which counts coin inflows is incremented. Similarly, when the player cashes out, a meter which counts coin outflows is incremented. However, because the player can now collect the credits purchased without risking any of the credits in a wager, the coin outflow meter does not reflect actual game activity. Therefore, the traditional calculation of game win percentage based on the ratio of coin inflow to coin outflow is improperly inflated.
Furthermore, video lottery systems, comprising many different games within a single cabinet, can create problems for typical accounting methods. Ideally, the accounting system should calculate game win percentage for each of the games because the theoretical win percentage may be different for each game. Thus, game accounting data must be maintained separately for each game. One way this has been accomplished is to provide separate accounting meters for each game in the cabinet. However, this solution requires a reconfiguration of the accounting system whenever games are added to the machine or the games within the machine are reordered. Although more flexibility could be added by allocating excess meter sets for each machine, this solution creates undesirable overhead. Moreover, one must still reconfigure the system when the games are reordered.
To further complicate the accounting problem, rules established by many gaming regulatory commissions require that all gaming locations account separately for all of the different forms of monetary value that can be accepted by modern gaming machines. Specifically, most jurisdictions require a complete audit of all wagers found in the coin and currency cash boxes. In machines equipped with coupon readers, the currency box may contain bar coded coupons of varying amounts in addition to cash. In the case of cashless wagers (e.g., those placed from player charge accounts), there may be no physical equivalent in either box. Yet the gaming locations's accounting system must provide an audit trail for each of these betting instruments. In addition, the rules require a separate accounting of the different forms of machine payouts. For example, where machine payouts are in the form of printed vouchers, the vouchers will be redeemed and stored at the redemption locations. Because the vouchers are relatively easy to forge or duplicate, the accounting system must also provide a record of these tickets against which payment can be made. To date, accounting system methodologies do not provide a convenient and unified mechanism for auditing betting activity in all of these different forms.
Therefore, there is a need for a fully general game accounting and monitoring system that keeps accurate game accounting data and maintains audit trails of gaming activity independent of the type of gaming machine and the forms of monetary value used by the gaming machine. In addition, there is a need for a game accounting and monitoring system that can accurately calculate the hopper level and game win percentage based on accounting data for all varieties of gaming machines.